The present disclosure relates to a coming-off stopping mechanism, a fixing device and an image forming apparatus.
Conventionally, an image forming apparatus of an electrographic manner includes a fixing device fixing a toner image onto a recording medium, such as a sheet.
For example, the fixing device includes a fixing roller rotatable around an axis center in which a halogen lamp is provided, and a pressuring roller rotatable around an axis center fixing a nip part between the fixing roller and the pressuring roller. The fixing device carries out fixing process heating the toner image on the sheet by feeding the sheet to the nip part. Moreover, the fixing device includes an annular heat insulating member fitted from the outside concentrically with the fixing roller, a bearing fitted at the outside of the annular heat insulating member and a C-shaped coming-off stopping ring stopping coming-off of the annular heat insulating member. The C-shaped coming-off stopping ring is fitted from the outside of the fixing roller and supported at three points on an outer circumference face of the fixing roller.
However, because the C-shaped coming-off stopping ring is fitted from the outside of the fixing roller, the C-shaped coming-off stopping ring may receive force in a rotating direction in accordance with rotation of the fixing roller, and thereby, a diameter of the C-shaped coming-off stopping ring may be broadened. As a result, the C-shaped coming-off stopping ring may be come off from the fixing roller. Moreover, because the C-shaped coming-off stopping ring is fitted while being rubbed on the outer circumference face of the fixing roller, the C-shaped coming-off stopping ring may damage the outer circumference face of the fixing roller.